2 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * Ssh client program. This program can be used to log into a remote machine.
6 * The software supports strong authentication, encryption, and forwarding
7 * of X11, TCP/IP, and authentication connections.
9 * As far as I am concerned, the code I have written for this software
10 * can be used freely for any purpose. Any derived versions of this
11 * software must be clearly marked as such, and if the derived work is
12 * incompatible with the protocol description in the RFC file, it must be
13 * called by a name other than "ssh" or "Secure Shell".
15 * Copyright (c) 1999 Niels Provos. All rights reserved.
17 * Modified to work with SSL by Niels Provos <provos@citi.umich.edu>
18 * in Canada (German citizen).
20 * Redistribution and use in source and binary forms, with or without
21 * modification, are permitted provided that the following conditions
23 * 1. Redistributions of source code must retain the above copyright
24 * notice, this list of conditions and the following disclaimer.
25 * 2. Redistributions in binary form must reproduce the above copyright
26 * notice, this list of conditions and the following disclaimer in the
27 * documentation and/or other materials provided with the distribution.
29 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
30 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
31 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
32 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
33 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
34 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
38 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
42 RCSID("$OpenBSD: ssh.c,v 1.69 2000/10/27 07:32:19 markus Exp $");
44 #include <openssl/evp.h>
45 #include <openssl/dsa.h>
46 #include <openssl/rsa.h>
62 #ifdef HAVE___PROGNAME
63 extern char *__progname;
64 #else /* HAVE___PROGNAME */
65 static const char *__progname = "ssh";
66 #endif /* HAVE___PROGNAME */
68 /* Flag indicating whether IPv4 or IPv6. This can be set on the command line.
69 Default value is AF_UNSPEC means both IPv4 and IPv6. */
71 int IPv4or6 = AF_INET;
73 int IPv4or6 = AF_UNSPEC;
76 /* Flag indicating whether debug mode is on. This can be set on the command line. */
79 /* Flag indicating whether a tty should be allocated */
82 /* don't exec a shell */
83 int no_shell_flag = 0;
87 * Flag indicating that nothing should be read from stdin. This can be set
88 * on the command line.
90 int stdin_null_flag = 0;
93 * Flag indicating that ssh should fork after authentication. This is useful
94 * so that the pasphrase can be entered manually, and then ssh goes to the
97 int fork_after_authentication_flag = 0;
100 * General data structure for command line options and options configurable
101 * in configuration files. See readconf.h.
106 * Name of the host we are connecting to. This is the name given on the
107 * command line, or the HostName specified for the user-supplied name in a
108 * configuration file.
112 /* socket address the host resolves to */
113 struct sockaddr_storage hostaddr;
116 * Flag to indicate that we have received a window change signal which has
117 * not yet been processed. This will cause a message indicating the new
118 * window size to be sent to the server a little later. This is volatile
119 * because this is updated in a signal handler.
121 volatile int received_window_change_signal = 0;
123 /* Value of argv[0] (set in the main program). */
126 /* Flag indicating whether we have a valid host private key loaded. */
127 int host_private_key_loaded = 0;
129 /* Host private key. */
130 RSA *host_private_key = NULL;
132 /* Original real UID. */
133 uid_t original_real_uid;
135 /* command to be executed */
138 /* Prints a help message to the user. This function never returns. */
143 fprintf(stderr, "Usage: %s [options] host [command]\n", av0);
144 fprintf(stderr, "Options:\n");
145 fprintf(stderr, " -l user Log in using this user name.\n");
146 fprintf(stderr, " -n Redirect input from /dev/null.\n");
147 fprintf(stderr, " -A Enable authentication agent forwarding.\n");
148 fprintf(stderr, " -a Disable authentication agent forwarding.\n");
150 fprintf(stderr, " -k Disable Kerberos ticket and AFS token forwarding.\n");
152 fprintf(stderr, " -X Enable X11 connection forwarding.\n");
153 fprintf(stderr, " -x Disable X11 connection forwarding.\n");
154 fprintf(stderr, " -i file Identity for RSA authentication (default: ~/.ssh/identity).\n");
155 fprintf(stderr, " -t Tty; allocate a tty even if command is given.\n");
156 fprintf(stderr, " -T Do not allocate a tty.\n");
157 fprintf(stderr, " -v Verbose; display verbose debugging messages.\n");
158 fprintf(stderr, " Multiple -v increases verbosity.\n");
159 fprintf(stderr, " -V Display version number only.\n");
160 fprintf(stderr, " -P Don't allocate a privileged port.\n");
161 fprintf(stderr, " -q Quiet; don't display any warning messages.\n");
162 fprintf(stderr, " -f Fork into background after authentication.\n");
163 fprintf(stderr, " -e char Set escape character; ``none'' = disable (default: ~).\n");
165 fprintf(stderr, " -c cipher Select encryption algorithm: "
168 fprintf(stderr, " -p port Connect to this port. Server must be on the same port.\n");
169 fprintf(stderr, " -L listen-port:host:port Forward local port to remote address\n");
170 fprintf(stderr, " -R listen-port:host:port Forward remote port to local address\n");
171 fprintf(stderr, " These cause %s to listen for connections on a port, and\n", av0);
172 fprintf(stderr, " forward them to the other side by connecting to host:port.\n");
173 fprintf(stderr, " -C Enable compression.\n");
174 fprintf(stderr, " -N Do not execute a shell or command.\n");
175 fprintf(stderr, " -g Allow remote hosts to connect to forwarded ports.\n");
176 fprintf(stderr, " -4 Use IPv4 only.\n");
177 fprintf(stderr, " -6 Use IPv6 only.\n");
178 fprintf(stderr, " -2 Force protocol version 2.\n");
179 fprintf(stderr, " -o 'option' Process the option as if it was read from a configuration file.\n");
184 * Connects to the given host using rsh (or prints an error message and exits
185 * if rsh is not available). This function never returns.
188 rsh_connect(char *host, char *user, Buffer * command)
193 log("Using rsh. WARNING: Connection will not be encrypted.");
194 /* Build argument list for rsh. */
196 args[i++] = _PATH_RSH;
197 /* host may have to come after user on some systems */
203 if (buffer_len(command) > 0) {
204 buffer_append(command, "\0", 1);
205 args[i++] = buffer_ptr(command);
209 for (i = 0; args[i]; i++) {
211 fprintf(stderr, " ");
212 fprintf(stderr, "%s", args[i]);
214 fprintf(stderr, "\n");
216 execv(_PATH_RSH, args);
221 int ssh_session(void);
222 int ssh_session2(void);
225 * Main program for the ssh client.
228 main(int ac, char **av)
230 int i, opt, optind, exit_status, ok;
231 u_short fwd_port, fwd_host_port;
232 char *optarg, *cp, buf[256];
234 struct passwd *pw, pwcopy;
236 uid_t original_effective_uid;
241 * Save the original real uid. It will be needed later (uid-swapping
242 * may clobber the real uid).
244 original_real_uid = getuid();
245 original_effective_uid = geteuid();
247 #ifdef HAVE_SETRLIMIT
248 /* If we are installed setuid root be careful to not drop core. */
249 if (original_real_uid != original_effective_uid) {
251 rlim.rlim_cur = rlim.rlim_max = 0;
252 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
253 fatal("setrlimit failed: %.100s", strerror(errno));
257 * Use uid-swapping to give up root privileges for the duration of
258 * option processing. We will re-instantiate the rights when we are
259 * ready to create the privileged port, and will permanently drop
260 * them when the port has been created (actually, when the connection
261 * has been made, as we may need to create the port several times).
263 temporarily_use_uid(original_real_uid);
266 * Set our umask to something reasonable, as some files are created
267 * with the default umask. This will make them world-readable but
268 * writable only by the owner, which is ok for all files for which we
269 * don't set the modes explicitly.
273 /* Save our own name. */
276 /* Initialize option structure to indicate that no values have been set. */
277 initialize_options(&options);
279 /* Parse command-line arguments. */
282 /* If program name is not one of the standard names, use it as host name. */
283 if (strchr(av0, '/'))
284 cp = strrchr(av0, '/') + 1;
288 if (strcasecmp(cp, "rsh") && strcasecmp(cp, "ssh") &&
289 strcasecmp(cp, "rlogin") && strcasecmp(cp, "slogin") &&
290 strcasecmp(cp, "remsh") &&
291 strcasecmp(cp, "rsh.exe") && strcasecmp(cp, "ssh.exe") &&
292 strcasecmp(cp, "rlogin.exe") && strcasecmp(cp, "slogin.exe") &&
293 strcasecmp(cp, "remsh.exe"))
295 if (strcmp(cp, "rsh") && strcmp(cp, "ssh") && strcmp(cp, "rlogin") &&
296 strcmp(cp, "slogin") && strcmp(cp, "remsh"))
300 for (optind = 1; optind < ac; optind++) {
301 if (av[optind][0] != '-') {
304 if ((cp = strchr(av[optind], '@'))) {
307 options.user = av[optind];
317 if (strchr("eilcpLRo", opt)) { /* options with arguments */
318 optarg = av[optind] + 2;
319 if (strcmp(optarg, "") == 0) {
320 if (optind >= ac - 1)
322 optarg = av[++optind];
331 options.protocol = SSH_PROTO_2;
343 fork_after_authentication_flag = 1;
347 options.forward_x11 = 0;
350 options.forward_x11 = 1;
353 options.gateway_ports = 1;
356 options.use_privileged_port = 0;
359 options.forward_agent = 0;
362 options.forward_agent = 1;
366 options.kerberos_tgt_passing = 0;
367 options.afs_token_passing = 0;
371 if (stat(optarg, &st) < 0) {
372 fprintf(stderr, "Warning: Identity file %s does not exist.\n",
376 if (options.num_identity_files >= SSH_MAX_IDENTITY_FILES)
377 fatal("Too many identity files specified (max %d)",
378 SSH_MAX_IDENTITY_FILES);
379 options.identity_files[options.num_identity_files++] =
386 if (0 == debug_flag) {
388 options.log_level = SYSLOG_LEVEL_DEBUG1;
389 } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) {
393 fatal("Too high debugging level.\n");
397 fprintf(stderr, "SSH Version %s, protocol versions %d.%d/%d.%d.\n",
399 PROTOCOL_MAJOR_1, PROTOCOL_MINOR_1,
400 PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2);
401 fprintf(stderr, "Compiled with SSL (0x%8.8lx).\n", SSLeay());
406 options.log_level = SYSLOG_LEVEL_QUIET;
409 if (optarg[0] == '^' && optarg[2] == 0 &&
410 (unsigned char) optarg[1] >= 64 && (unsigned char) optarg[1] < 128)
411 options.escape_char = (unsigned char) optarg[1] & 31;
412 else if (strlen(optarg) == 1)
413 options.escape_char = (unsigned char) optarg[0];
414 else if (strcmp(optarg, "none") == 0)
415 options.escape_char = -2;
417 fprintf(stderr, "Bad escape character '%s'.\n", optarg);
422 if (ciphers_valid(optarg)) {
424 options.ciphers = xstrdup(optarg);
425 options.cipher = SSH_CIPHER_ILLEGAL;
428 Cipher *c = cipher_by_name(optarg);
429 if (c == NULL || c->number < 0) {
430 fprintf(stderr, "Unknown cipher type '%s'\n", optarg);
433 options.cipher = c->number;
437 options.port = atoi(optarg);
440 options.user = optarg;
443 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
444 &fwd_host_port) != 3 &&
445 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
446 &fwd_host_port) != 3) {
447 fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg);
451 add_remote_forward(&options, fwd_port, buf, fwd_host_port);
454 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
455 &fwd_host_port) != 3 &&
456 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
457 &fwd_host_port) != 3) {
458 fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg);
462 add_local_forward(&options, fwd_port, buf, fwd_host_port);
465 options.compression = 1;
476 if (process_config_line(&options, host ? host : "", optarg,
477 "command-line", 0, &dummy) != 0)
485 /* Check that we got a host name. */
489 SSLeay_add_all_algorithms();
491 /* Initialize the command to execute on remote host. */
492 buffer_init(&command);
495 * Save the command to execute on the remote host in a buffer. There
496 * is no limit on the length of the command, except by the maximum
497 * packet size. Also sets the tty flag if there is no command.
500 /* No command specified - execute shell on a tty. */
503 /* A command has been specified. Store it into the
505 for (i = optind; i < ac; i++) {
507 buffer_append(&command, " ", 1);
508 buffer_append(&command, av[i], strlen(av[i]));
512 /* Cannot fork to background if no command. */
513 if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag)
514 fatal("Cannot fork into background without a command to execute.");
516 /* Allocate a tty by default if no command specified. */
517 if (buffer_len(&command) == 0)
520 /* Do not allocate a tty if stdin is not a tty. */
521 if (!isatty(fileno(stdin))) {
523 fprintf(stderr, "Pseudo-terminal will not be allocated because stdin is not a terminal.\n");
531 pw = getpwuid(original_real_uid);
533 fprintf(stderr, "You don't exist, go away!\n");
536 /* Take a copy of the returned structure. */
537 memset(&pwcopy, 0, sizeof(pwcopy));
538 pwcopy.pw_name = xstrdup(pw->pw_name);
539 pwcopy.pw_passwd = xstrdup(pw->pw_passwd);
540 pwcopy.pw_uid = pw->pw_uid;
541 pwcopy.pw_gid = pw->pw_gid;
542 #ifdef HAVE_PW_CLASS_IN_PASSWD
543 pwcopy.pw_class = xstrdup(pw->pw_class);
545 pwcopy.pw_dir = xstrdup(pw->pw_dir);
546 pwcopy.pw_shell = xstrdup(pw->pw_shell);
549 /* Initialize "log" output. Since we are the client all output
550 actually goes to the terminal. */
551 log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 0);
553 /* Read per-user configuration file. */
554 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, SSH_USER_CONFFILE);
555 read_config_file(buf, host, &options);
557 /* Read systemwide configuration file. */
558 read_config_file(HOST_CONFIG_FILE, host, &options);
560 /* Fill configuration defaults. */
561 fill_default_options(&options);
564 log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 0);
566 /* check if RSA support exists */
567 if ((options.protocol & SSH_PROTO_1) &&
569 log("%s: no RSA support in libssl and libcrypto. See ssl(8).",
571 log("Disabling protocol version 1");
572 options.protocol &= ~ (SSH_PROTO_1|SSH_PROTO_1_PREFERRED);
574 if (! options.protocol & (SSH_PROTO_1|SSH_PROTO_2)) {
575 fprintf(stderr, "%s: No protocol version available.\n",
580 if (options.user == NULL)
581 options.user = xstrdup(pw->pw_name);
583 if (options.hostname != NULL)
584 host = options.hostname;
586 /* Disable rhosts authentication if not running as root. */
588 /* Ignore uid if running under Windows */
589 if (!options.use_privileged_port) {
591 if (original_effective_uid != 0 || !options.use_privileged_port) {
593 options.rhosts_authentication = 0;
594 options.rhosts_rsa_authentication = 0;
597 * If using rsh has been selected, exec it now (without trying
598 * anything else). Note that we must release privileges first.
600 if (options.use_rsh) {
602 * Restore our superuser privileges. This must be done
603 * before permanently setting the uid.
607 /* Switch to the original uid permanently. */
608 permanently_set_uid(original_real_uid);
611 rsh_connect(host, options.user, &command);
612 fatal("rsh_connect returned");
614 /* Restore our superuser privileges. */
618 * Open a connection to the remote host. This needs root privileges
619 * if rhosts_{rsa_}authentication is enabled.
622 ok = ssh_connect(host, &hostaddr, options.port,
623 options.connection_attempts,
624 !options.rhosts_authentication &&
625 !options.rhosts_rsa_authentication,
627 options.proxy_command);
630 * If we successfully made the connection, load the host private key
631 * in case we will need it later for combined rsa-rhosts
632 * authentication. This must be done before releasing extra
633 * privileges, because the file is only readable by root.
635 if (ok && (options.protocol & SSH_PROTO_1)) {
637 host_private_key = RSA_new();
639 k.rsa = host_private_key;
640 if (load_private_key(HOST_KEY_FILE, "", &k, NULL))
641 host_private_key_loaded = 1;
644 * Get rid of any extra privileges that we may have. We will no
645 * longer need them. Also, extra privileges could make it very hard
646 * to read identity files and other non-world-readable files from the
647 * user's home directory if it happens to be on a NFS volume where
648 * root is mapped to nobody.
652 * Note that some legacy systems need to postpone the following call
653 * to permanently_set_uid() until the private hostkey is destroyed
654 * with RSA_free(). Otherwise the calling user could ptrace() the
655 * process, read the private hostkey and impersonate the host.
656 * OpenBSD does not allow ptracing of setuid processes.
658 permanently_set_uid(original_real_uid);
661 * Now that we are back to our own permissions, create ~/.ssh
662 * directory if it doesn\'t already exist.
664 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, SSH_USER_DIR);
665 if (stat(buf, &st) < 0)
666 if (mkdir(buf, 0700) < 0)
667 error("Could not create directory '%.200s'.", buf);
669 /* Check if the connection failed, and try "rsh" if appropriate. */
671 if (options.port != 0)
672 log("Secure connection to %.100s on port %hu refused%.100s.",
674 options.fallback_to_rsh ? "; reverting to insecure method" : "");
676 log("Secure connection to %.100s refused%.100s.", host,
677 options.fallback_to_rsh ? "; reverting to insecure method" : "");
679 if (options.fallback_to_rsh) {
680 rsh_connect(host, options.user, &command);
681 fatal("rsh_connect returned");
685 /* Expand ~ in options.identity_files. */
687 for (i = 0; i < options.num_identity_files; i++)
688 options.identity_files[i] =
689 tilde_expand_filename(options.identity_files[i], original_real_uid);
690 for (i = 0; i < options.num_identity_files2; i++)
691 options.identity_files2[i] =
692 tilde_expand_filename(options.identity_files2[i], original_real_uid);
693 /* Expand ~ in known host file names. */
694 options.system_hostfile = tilde_expand_filename(options.system_hostfile,
696 options.user_hostfile = tilde_expand_filename(options.user_hostfile,
698 options.system_hostfile2 = tilde_expand_filename(options.system_hostfile2,
700 options.user_hostfile2 = tilde_expand_filename(options.user_hostfile2,
703 /* Log into the remote system. This never returns if the login fails. */
704 ssh_login(host_private_key_loaded, host_private_key,
705 host, (struct sockaddr *)&hostaddr, original_real_uid);
707 /* We no longer need the host private key. Clear it now. */
708 if (host_private_key_loaded)
709 RSA_free(host_private_key); /* Destroys contents safely */
711 exit_status = compat20 ? ssh_session2() : ssh_session();
717 x11_get_proto(char *proto, int proto_len, char *data, int data_len)
723 if (options.xauth_location) {
724 /* Try to get Xauthority information for the display. */
725 snprintf(line, sizeof line, "%.100s list %.200s 2>/dev/null",
726 options.xauth_location, getenv("DISPLAY"));
727 f = popen(line, "r");
728 if (f && fgets(line, sizeof(line), f) &&
729 sscanf(line, "%*s %s %s", proto, data) == 2)
735 * If we didn't get authentication data, just make up some
736 * data. The forwarding code will check the validity of the
737 * response anyway, and substitute this data. The X11
738 * server, however, will ignore this fake data and use
739 * whatever authentication mechanisms it was using otherwise
740 * for the local connection.
745 strlcpy(proto, "MIT-MAGIC-COOKIE-1", proto_len);
746 for (i = 0; i < 16; i++) {
749 snprintf(data + 2 * i, data_len - 2 * i, "%02x", rand & 0xff);
767 /* Enable compression if requested. */
768 if (options.compression) {
769 debug("Requesting compression at level %d.", options.compression_level);
771 if (options.compression_level < 1 || options.compression_level > 9)
772 fatal("Compression level must be from 1 (fast) to 9 (slow, best).");
774 /* Send the request. */
775 packet_start(SSH_CMSG_REQUEST_COMPRESSION);
776 packet_put_int(options.compression_level);
779 type = packet_read(&plen);
780 if (type == SSH_SMSG_SUCCESS)
781 packet_start_compression(options.compression_level);
782 else if (type == SSH_SMSG_FAILURE)
783 log("Warning: Remote host refused compression.");
785 packet_disconnect("Protocol error waiting for compression response.");
787 /* Allocate a pseudo tty if appropriate. */
789 debug("Requesting pty.");
791 /* Start the packet. */
792 packet_start(SSH_CMSG_REQUEST_PTY);
794 /* Store TERM in the packet. There is no limit on the
795 length of the string. */
799 packet_put_string(cp, strlen(cp));
801 /* Store window size in the packet. */
802 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
803 memset(&ws, 0, sizeof(ws));
804 packet_put_int(ws.ws_row);
805 packet_put_int(ws.ws_col);
806 packet_put_int(ws.ws_xpixel);
807 packet_put_int(ws.ws_ypixel);
809 /* Store tty modes in the packet. */
810 tty_make_modes(fileno(stdin));
812 /* Send the packet, and wait for it to leave. */
816 /* Read response from the server. */
817 type = packet_read(&plen);
818 if (type == SSH_SMSG_SUCCESS) {
821 } else if (type == SSH_SMSG_FAILURE)
822 log("Warning: Remote host failed or refused to allocate a pseudo tty.");
824 packet_disconnect("Protocol error waiting for pty request response.");
826 /* Request X11 forwarding if enabled and DISPLAY is set. */
827 if (options.forward_x11 && getenv("DISPLAY") != NULL) {
828 char proto[512], data[512];
829 /* Get reasonable local authentication information. */
830 x11_get_proto(proto, sizeof proto, data, sizeof data);
831 /* Request forwarding with authentication spoofing. */
832 debug("Requesting X11 forwarding with authentication spoofing.");
833 x11_request_forwarding_with_spoofing(0, proto, data);
835 /* Read response from the server. */
836 type = packet_read(&plen);
837 if (type == SSH_SMSG_SUCCESS) {
839 } else if (type == SSH_SMSG_FAILURE) {
840 log("Warning: Remote host denied X11 forwarding.");
842 packet_disconnect("Protocol error waiting for X11 forwarding");
845 /* Tell the packet module whether this is an interactive session. */
846 packet_set_interactive(interactive, options.keepalives);
848 /* Clear agent forwarding if we don\'t have an agent. */
849 authfd = ssh_get_authentication_socket();
851 options.forward_agent = 0;
853 ssh_close_authentication_socket(authfd);
855 /* Request authentication agent forwarding if appropriate. */
856 if (options.forward_agent) {
857 debug("Requesting authentication agent forwarding.");
858 auth_request_forwarding();
860 /* Read response from the server. */
861 type = packet_read(&plen);
862 packet_integrity_check(plen, 0, type);
863 if (type != SSH_SMSG_SUCCESS)
864 log("Warning: Remote host denied authentication agent forwarding.");
866 /* Initiate local TCP/IP port forwardings. */
867 for (i = 0; i < options.num_local_forwards; i++) {
868 debug("Connections to local port %d forwarded to remote address %.200s:%d",
869 options.local_forwards[i].port,
870 options.local_forwards[i].host,
871 options.local_forwards[i].host_port);
872 channel_request_local_forwarding(options.local_forwards[i].port,
873 options.local_forwards[i].host,
874 options.local_forwards[i].host_port,
875 options.gateway_ports);
878 /* Initiate remote TCP/IP port forwardings. */
879 for (i = 0; i < options.num_remote_forwards; i++) {
880 debug("Connections to remote port %d forwarded to local address %.200s:%d",
881 options.remote_forwards[i].port,
882 options.remote_forwards[i].host,
883 options.remote_forwards[i].host_port);
884 channel_request_remote_forwarding(options.remote_forwards[i].port,
885 options.remote_forwards[i].host,
886 options.remote_forwards[i].host_port);
889 /* If requested, let ssh continue in the background. */
890 if (fork_after_authentication_flag)
891 if (daemon(1, 1) < 0)
892 fatal("daemon() failed: %.200s", strerror(errno));
895 * If a command was specified on the command line, execute the
896 * command now. Otherwise request the server to start a shell.
898 if (buffer_len(&command) > 0) {
899 int len = buffer_len(&command);
902 debug("Sending command: %.*s", len, buffer_ptr(&command));
903 packet_start(SSH_CMSG_EXEC_CMD);
904 packet_put_string(buffer_ptr(&command), buffer_len(&command));
908 debug("Requesting shell.");
909 packet_start(SSH_CMSG_EXEC_SHELL);
914 /* Enter the interactive session. */
915 return client_loop(have_tty, tty_flag ? options.escape_char : -1, 0);
922 /* Initiate local TCP/IP port forwardings. */
923 for (i = 0; i < options.num_local_forwards; i++) {
924 debug("Connections to local port %d forwarded to remote address %.200s:%d",
925 options.local_forwards[i].port,
926 options.local_forwards[i].host,
927 options.local_forwards[i].host_port);
928 channel_request_local_forwarding(options.local_forwards[i].port,
929 options.local_forwards[i].host,
930 options.local_forwards[i].host_port,
931 options.gateway_ports);
935 extern void client_set_session_ident(int id);
938 client_init(int id, void *arg)
941 debug("client_init id %d arg %d", id, (int)arg);
952 /* Store window size in the packet. */
953 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
954 memset(&ws, 0, sizeof(ws));
956 channel_request_start(id, "pty-req", 0);
957 packet_put_cstring(cp);
958 packet_put_int(ws.ws_col);
959 packet_put_int(ws.ws_row);
960 packet_put_int(ws.ws_xpixel);
961 packet_put_int(ws.ws_ypixel);
962 packet_put_cstring(""); /* XXX: encode terminal modes */
964 /* XXX wait for reply */
966 if (options.forward_x11 &&
967 getenv("DISPLAY") != NULL) {
968 char proto[512], data[512];
969 /* Get reasonable local authentication information. */
970 x11_get_proto(proto, sizeof proto, data, sizeof data);
971 /* Request forwarding with authentication spoofing. */
972 debug("Requesting X11 forwarding with authentication spoofing.");
973 x11_request_forwarding_with_spoofing(id, proto, data);
974 /* XXX wait for reply */
977 len = buffer_len(&command);
981 debug("Sending command: %.*s", len, buffer_ptr(&command));
982 channel_request_start(id, "exec", 0);
983 packet_put_string(buffer_ptr(&command), len);
986 channel_request(id, "shell", 0);
988 /* channel_callback(id, SSH2_MSG_OPEN_CONFIGMATION, client_init, 0); */
990 /* register different callback, etc. XXX */
991 client_set_session_ident(id);
997 int window, packetmax, id;
1000 if (stdin_null_flag) {
1001 in = open("/dev/null", O_RDONLY);
1003 in = dup(STDIN_FILENO);
1005 out = dup(STDOUT_FILENO);
1006 err = dup(STDERR_FILENO);
1008 if (in < 0 || out < 0 || err < 0)
1009 fatal("dup() in/out/err failed");
1011 /* enable nonblocking unless tty */
1019 /* should be pre-session */
1022 /* If requested, let ssh continue in the background. */
1023 if (fork_after_authentication_flag)
1024 if (daemon(1, 1) < 0)
1025 fatal("daemon() failed: %.200s", strerror(errno));
1027 window = CHAN_SES_WINDOW_DEFAULT;
1028 packetmax = CHAN_SES_PACKET_DEFAULT;
1034 "session", SSH_CHANNEL_OPENING, in, out, err,
1035 window, packetmax, CHAN_EXTENDED_WRITE,
1036 xstrdup("client-session"), /*nonblock*/0);
1039 channel_register_callback(id, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, client_init, (void *)0);
1041 return client_loop(tty_flag, tty_flag ? options.escape_char : -1, id);